Exactly right. The problem with the Chevron doctrine is that as it has been interpreted and applied, it works as a one-way ratchet in favor of ever expanding agency authority.
It’s one thing to defer to an agency’s interpretation of issues when they truly involve technical matters beyond the scope of an average judge. It’s quite another to defer to an agency interpretation that expands it’s own jurisdiction, simply because the agency wants more power, or thinks it can “do better.”
In the latter circumstance, the Court should say “no,” and tell the agency that it needs to get Congress to explicitly approve the expansion of its authority.
Another example would be the BATFE’s recent redefinition of a firearm receiver to include 80% receivers. The 80% rule was a reasonable compromise that the regime’s gun grabbers can’t stand, so now they risk having all AR style two-part receivers being ruled not to be firearms under the GCA, which some judges have already ruled.
The problem with that is that you are assigning to Congress powers it does not have.